Tom Bendix

Background: In the treatment of chronic back pain, cognitive methods are attracting increased attention due to evidence of effectiveness similar to that of traditional therapies. The purpose of this study was to compare the effectiveness of performing a cognitive intervention based on a non-injury model with that of a symptom-based physical training method on the outcomes of low back pain (LBP), activity limitation, LBP attitudes (fear-avoidance beliefs and back beliefs), physical activity levels, sick leave, and quality of life, in chronic LBP patients. Methods: The study was a pragmatic, single-blind, randomised, parallel-group trial. Patients with chronic/recurrent LBP were randomised to one of the following treatments: 1. Educational programme : the emphasis was on creating confidence that the back is strong, that loads normally do not cause any damage despite occasional temporary pain, that reducing the focus on the pain might facilitate more natural and less painful movements, and that it is beneficial to stay physically active. 2. Individual symptom-based physical training programme : directional-preference exercises for those centralising their pain with repetitive movements; 'stabilising exercises' for those deemed 'unstable' based on specific tests; or intensive dynamic exercises for the remaining patients. Follow-up questionnaires (examiner-blinded) were completed at 2, 6 and 12 months. The main statistical test was an ANCOVA adjusted for baseline values. Results: A total of 207 patients participated with the median age of 39 years (IQR 33-47); 52% were female, 105 were randomised to the educational programme and 102 to the physical training programme. The two groups were comparable at baseline. For the primary outcome measures, there was a non-significant trend towards activity limitation being reduced mostly in the educational programme group, although of doubtful clinical relevance. Regarding secondary outcomes, improvement in fear-avoidance beliefs was also better in the educational programme group. All other variables were about equally influenced by the two treatments. The median number of treatment sessions was 3 for the educational programme group and 6 for the physical training programme group. Conclusions: An educational approach to treatment for chronic LBP resulted in at least as good outcomes as a symptom-based physical training method, despite fewer treatment sessions. Trial registration: Clinicaltrials.gov: # NCT00410319

Active approaches including both specific and unspecific exercise are probably the most widely recommended treatment for patients with chronic low back pain but it is not known exactly which types of exercise provide the most benefit. Nordic Walking - power walking using ski poles - is a popular and fast growing type of exercise in Northern Europe that has been shown to improve cardiovascular metabolism. Until now, no studies have been performed to investigate whether Nordic Walking has beneficial effects in relation to back pain.

Vertebral endplate signal changes (VESC) are more common among patients with low back pain (LBP) and/or sciatica than in people who are not seeking care for back pain. The distribution and characteristics of VESC have been described in people from clinical and non-clinical populations. However, while the clinical course of VESC has been studied in patients, the natural course in the general population has not been reported. The objectives of this prospective observational study were to describe: 1) the distribution and characteristics of VESC in the lumbar spine, 2) its association with disc degeneration, and 3) its natural course from 40 to 44 years of age.

Cross-sectional study of a general-population sample. The aim was to test the hypothesis that moderate disc degeneration (DD) is stronger associated with low back pain (LBP) than severe degeneration, and also to identify a possible dose-response relationship between numbers of degenerated discs and LBP. Among many clinicians there has been a belief that DD initially causes pain because of the penetration of fluid nuclear material through annular fissures, and that pain eventually resolves as the nucleus becomes fibrotic and can no longer penetrate the fissures. From a population-based cohort of 412 individuals, all aged 40, three groups were created for a primary analysis: those with exclusively normal discs (white nuclei on a T2-weighted MRI), those with moderate DD (grey) + normal, and those with severely degenerated (black) + normal discs. The number of individuals reporting LBP during the past year (the most relevant for chronic/intermittent pain) and the past month were separately related to DD. Second, a possible dose-response in terms of numbers of abnormal discs was analyzed. The percentage of people with LBP was virtually not influenced by grey discs, where the fraction with pain during the past year was close to 69% irrespective of the presence or number of grey discs. Black discs, however, increased the corresponding fraction from 60%, if no black discs, to 86% for those with 2 (odds ratio of 2 per number of black disc). The risk for LBP during the past year attributed to black discs was 11%. The data could not support the hypothesis that severely degenerated discs are "burned out" and become less painful. People with black discs had a higher prevalence of LBP compared to those with grey or normal discs, the latter 2 being equally often painful.

Recently, the MRI finding of "Modic changes" has been identified as pathologic spinal condition that probably reflects a vertebral inflammatory process (VIP), which coincides with spinal pain in most. We hypothesized that heavy smoking in combination with macro- or repeated microtrauma could lead to VIP. The objectives were to investigate if combinations of self-reported heavy smoking, hard physical work, and overweight would be more strongly linked with VIP than with other spinal conditions, such as degenerated discs and non-specific low back pain (LBP).

Study Design. A method comparison study. Objective. To investigate the effect of body position and axial load of the lumbar spine on disc height, lumbar lordosis, and dural sac cross-sectional area (DCSA). Summary of Background Data. The effects of flexion and extension on spinal canal diameters and DCSA are well documented. However, the effects of axial loading, achieved by upright standing or by a compression device, are still unclear. Methods. Patients with lumbar spinal stenosis were examined in 2 separate studies, including 16 and 20 patients, respectively. In section 1, magnetic resonance imaging (MRI) scans were performed during upright standing and supine positions with and without axial load. In section 2, MRI scans were performed exclusively in supine positions, one with flexion of the lumbar spine (psoas-relaxed position), an extended position (legs straight), and an extended position with applied axial loading. Disc height, lumbar lordosis, and DCSA were measured and the different positions were compared. Results. In section 1, the only significant difference between positions was a reduced lumbar lordosis during standing when compared with lying (P = 0.04), most probably a consequence of precautions taken to secure immobility during the vertical scans. This seemingly makes our standing posture less valuable as a standard of reference. In section 2, DCSA was reduced at all 5 lumbar levels after extension, and further reduced at 2 levels after adding compression (P < 0.05). Significant reductions of disc height were found at 3 motion segments and of DCSA at 11 segments after compression, but these changes were never seen in the same motion segment. Conclusion. Horizontal MRI with the patient supine and the legs straightened was comparable to vertical MRI whether axial compression was added or not. Extensionwas the dominant cause rather than compression in reducing DCSA. Axial load was not considered to have a clinically relevant effect on spinal canal diameters.

Because training of the lumbar muscles is a commonly recommended intervention in low back pain (LBP), it is important to clarify whether lumbar muscle atrophy is related to LBP. Fat infiltration seems to be a late stage of muscular degeneration, and can be measured in a non-invasive manner using magnetic resonance imaging. The purpose of this study was to investigate if fat infiltration in the lumbar multifidus muscles (LMM) is associated with LBP in adults and adolescents. In total, 412 adults (40-year-olds) and 442 adolescents (13-year-olds) from the general Danish population participated in this cross-sectional cohort study. People with LBP were identified through questionnaires. Using MRI, fat infiltration of the LMM was visually graded as none, slight or severe. Odds ratios were calculated for both age groups, taking into account sex, body composition and leisure time physical activity for both groups, and physical workload (in adults only) or daily bicycling (in adolescents only). Fat infiltration was noted in 81% of the adults but only 14% of the adolescents. In the adults, severe fat infiltration was strongly associated with ever having had LBP (OR 9.2; 95% CI 2.0–43.2), and with having LBP in the past year (OR 4.1; 1.5–11.2), but there was no such association in adolescents. None of the investigated moderating factors had an obvious effect on the OR in the adults. Fat infiltration in the LMM is strongly associated with LBP in adults only. However, it will be necessary to quantify these measurements objectively and to investigate the direction of this link longitudinally in order to determine if the abnormal muscle is the cause of LBP or vice versa.

Low back pain created a dramatic increase in sick leave from 1970-95 despite of no pain-relevant biological changes of the back. An update of several disc-related pathologies is presented. Especially discovering the significance of Modic changes and a new muscle-function understanding contribute to a modernized view on pain mechanisms. Generally, traditional treatment modalities have an effect wise sparse influence on natural history over time. Subgroup identification is a central issue in modern research, because the effect of treatment can be very different across such groups.